Animate a point along a line
This example animates the position of a point by updating a GeoJSON source on each frame.
It first defines the animation as a GeoJSON object. Then it adds a GeoJSON source referring to that GeoJSON, and adds a circle layer that uses that source.
Finally, it starts the animation with the JavaScript window.requestAnimationFrame() method to continuously update the GeoJSON object, resulting in a moving circle on the map.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Animate a point along a line</title>
<meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no">
<link href="https://api.mapbox.com/mapbox-gl-js/v3.8.0/mapbox-gl.css" rel="stylesheet">
<script src="https://api.mapbox.com/mapbox-gl-js/v3.8.0/mapbox-gl.js"></script>
<style>
body { margin: 0; padding: 0; }
#map { position: absolute; top: 0; bottom: 0; width: 100%; }
</style>
</head>
<body>
<div id="map"></div>
<script>
// TO MAKE THE MAP APPEAR YOU MUST
// ADD YOUR ACCESS TOKEN FROM
// https://account.mapbox.com
mapboxgl.accessToken = 'YOUR_MAPBOX_ACCESS_TOKEN';
const map = new mapboxgl.Map({
container: 'map',
// Choose from Mapbox's core styles, or make your own style with Mapbox Studio
style: 'mapbox://styles/mapbox/streets-v12',
center: [0, 0],
zoom: 2
});
const radius = 20;
function pointOnCircle(angle) {
return {
'type': 'Point',
'coordinates': [Math.cos(angle) * radius, Math.sin(angle) * radius]
};
}
map.on('load', () => {
// Add a source and layer displaying a point which will be animated in a circle.
map.addSource('point', {
'type': 'geojson',
'data': pointOnCircle(0)
});
map.addLayer({
'id': 'point',
'source': 'point',
'type': 'circle',
'paint': {
'circle-radius': 10,
'circle-color': '#007cbf'
}
});
function animateMarker(timestamp) {
// Update the data to a new position based on the animation timestamp. The
// divisor in the expression `timestamp / 1000` controls the animation speed.
map.getSource('point').setData(pointOnCircle(timestamp / 1000));
// Request the next frame of the animation.
requestAnimationFrame(animateMarker);
}
// Start the animation.
animateMarker(0);
});
</script>
</body>
</html>
This code snippet will not work as expected until you replace
YOUR_MAPBOX_ACCESS_TOKEN with an access token from your Mapbox account.import React, { useEffect, useRef } from 'react';
import mapboxgl from 'mapbox-gl';
import 'mapbox-gl/dist/mapbox-gl.css';
const MapboxExample = () => {
const mapContainerRef = useRef();
const mapRef = useRef();
useEffect(() => {
// TO MAKE THE MAP APPEAR YOU MUST
// ADD YOUR ACCESS TOKEN FROM
// https://account.mapbox.com
mapboxgl.accessToken = 'YOUR_MAPBOX_ACCESS_TOKEN';
mapRef.current = new mapboxgl.Map({
container: 'map',
style: 'mapbox://styles/mapbox/streets-v12',
center: [0, 0],
zoom: 2
});
const radius = 20;
function pointOnCircle(angle) {
return {
type: 'Point',
coordinates: [Math.cos(angle) * radius, Math.sin(angle) * radius]
};
}
mapRef.current.on('load', () => {
mapRef.current.addSource('point', {
type: 'geojson',
data: pointOnCircle(0)
});
mapRef.current.addLayer({
id: 'point',
source: 'point',
type: 'circle',
paint: {
'circle-radius': 10,
'circle-color': '#007cbf'
}
});
function animateMarker(timestamp) {
mapRef.current
.getSource('point')
.setData(pointOnCircle(timestamp / 1000));
requestAnimationFrame(animateMarker);
}
animateMarker(0);
});
}, []);
return <div id="map" ref={mapContainerRef} style={{ height: '100%' }}></div>;
};
export default MapboxExample;
This code snippet will not work as expected until you replace
YOUR_MAPBOX_ACCESS_TOKEN with an access token from your Mapbox account.Was this example helpful?